Implement fixpoint iteration for escape analysis.

src/hydrogen-escape-analysis.h

 // Copyright 2013 the V8 project authors. All rights reserved.
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 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
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@@ skipping 52 matching lines @@
   HValue* NewMapCheckAndInsert(HCapturedObject* state, HCheckMaps* mapcheck);
 
   HCapturedObject* StateAt(HBasicBlock* block) {
     return block_states_.at(block->block_id());
   }
 
   void SetStateAt(HBasicBlock* block, HCapturedObject* state) {
     block_states_.Set(block->block_id(), state);
   }
 
+  // Maximum number of escape analysis iterations.
+  static const int kMaxFixpointIterationCount = 2;

[titzer, 2013/09/30 11:38:06]

How about a flag?

[Michael Starzinger, 2013/10/16 08:40:13]

Done.

+
   // List of allocations captured during collection phase.
   ZoneList<HInstruction*> captured_;
 
   // Number of captured objects on which scalar replacement was done.
   int number_of_objects_;
 
   // Number of scalar values tracked during scalar replacement phase.
   int number_of_values_;
   int cumulative_values_;
 
   // Map of block IDs to the data-flow state at block entry during the
   // scalar replacement phase.
   ZoneList<HCapturedObject*> block_states_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_ESCAPE_ANALYSIS_H_